logout and clear

start this script in .bash_logout!

#!/bin/bash
if [ -z "`tty|grep tty`" ]; then exit 0; fi
    TTY=`tty|tail -c2`
    if [ $TTY = "1" ]; then
    chvt 2;
    chvt $TTY;
else
    chvt 1
    chvt $TTY
fi